This invention relates to reusable shipping containers and more particularly, it concerns a panel retaining clamp arrangement by which five or more rectangular panels of plywood or similar material may be retained in an erect box-like container or in a compact stacked condition for storage or shipment with the full complement of clamping devices needed to effect the erected container.
In the transportation and storage of a wide range of commodities, shipping pallets and pallet containers are used extensively to facilitate handling by fork-lift vehicles, cranes or other such devices during loading or unloading operations. Although simple pallets in which a floor or deck panel is supported on skids or chocks to accommodate the tines of fork-lift devices have in the past and continue to supply the handling needs for shipping and storing many types of goods and materials, pallet containers in which the handled goods are partially or completely enclosed have such obvious advantages as increased capability for stacking and accommodation to predetermined spatial dimensions, not to mention the protection and containment features of an enclosure as distinguished from a simple planar support.
The major drawbacks with pallet containers heretofore available is added cost particularly in the continued handling, storage and transportation of the containers themselves when they are not in use for the transportation or storage of commercial goods. While the initial costs of pallet container manufacture are also significant, such initial costs, at least to the shipping and warehousing industries, are predictable and readily accommodated by the appropriate pricing of shipping and storing services. Empty pallet containers, on the other hand, represent a continuing and widely variable expense to such industries and ultimately to the public at large.
The problems associated with pallet containers have been partially solved by the use of reusable collapsible containers which reduce substantially the storing and shipping space requirements for the empty containers. Prior designs of such reusable and collapsible pallet containers, however, have involved trade-off between relatively high costs incident to satisfaction of such attributes as strength needed for the shipping of heavy or delicate goods and products, accommodation to diverse container sizes, ease of conversion between collapsed and erected states, and durability necessary to stand up under rough handling, as against reduced manufacturing and handling costs resulting in limitations on either the nature of goods capable of shipment, restriction on container size variation, and reduced facility for stacking without damage to or reliability on the contained goods for support of successive stacking tiers. Most collapsible shipping pallet containers tend to favor the latter criteria with the result that reusable pallet containers have enjoyed only limited acceptance and then only with special types of cargo.
There is a need, therefore, for improvements in the field of collapsible pallet containers to provide, without significant added expense, increased ruggedness and strength, adaptability to a wider range of cargos, and increased ease of convertability between erect and collapsed states.